The engineer has spent one year working in the US and discovered how things_______ overseas.

Mrs Smith, keep an eye on your child. Don’t leave him around the street.— Thanks for reminding me.

Two men ___ into my flat. One of them threatened me with a knife while the other tied me up.

I wonder if I ________ smoke here.—No，you ________.You see,there is a “NO SMOKING”sign here.

When I got on the bus,I_____I had left my wallet at home.[ ]